| (57) A method of drying a web of paper (12) emerging from a press section (14) of a papermaking
machine comprises the steps of:
transferring the web (12) from the press section to a first dryer section (16);
initiating the drying of a first side (18) of the web during passage of the web through
the first dryer section (16);
transferring the web (12) between the first dryer section (16) and a downstream second
dryer section (22) such that the web is reversed so that drying of the second side
(24) of the web is initiated during passage of the web through the second dryer section
(22), and
transferring the web (12) between subsequent dryer sections (118, 120, 122) such that
the first and second sides (18, 24) of the web (12) are alternately exposed to the
drying effect of the subsequent dryer sections (118, 120, 122) in sequence.
Each dryer section (16, 22, 118, 120, 122) includes a plurality of dryers (32-42,
58-63, 94-95) arranged in a single tier, a plurality of transfer rolls (44-54, 64-70,
100-106) each of which is disposed between and in close proximity to adjacent dryers,
and a felt (56, 72, 110) extending alternately past each dryer and transfer roll in
serpentine configuration such that the web is held between the felt and each dryer
and the felt is disposed between the web and each transfer roll. Vacuum rolls are used as said transfer rolls and a vacuum within the range of
0,249 - 2.49 kPa (1 - 10 inches WC) is applied in the vacuum rolls so as to restrain
the web during drying.
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